fuse blows, passenger mirror

Did you recently install speakers in the door?

Power mirrors typically "share" a wire. That means that there is one wire common between both mirrors. It sounds like one of the non-common wires is grounded - therefore when you apply 12vdc to the shared wire the other mirror moves, but when you apply voltage to the passenger mirror the fuse blows. Did you recently install speakers in the passenger door or do any other work over there?Kevin Pierson

I think your best first move would be to unplug the mirror in the door panel. If it still blows it will eliminate the mirror itself from being the issue(which it most likely is).Mike M2

Tech Manager

CS Dealer Services

The fact that the passenger mirror moves when doing some adjusting of the driver mirror leads me to believe the problem is going to be switch related.  But for troubleshooting, as mentioned earlier, try disconnecting the passenger mirror and go from there.

Disconnect the mirror or try to look inside the door tube (both sides) for a broken wire or two with insulation mangled.

What you have is 100% definitely a short-to-ground.. Whats happening is that the power wire in your passenger side mirror circuit is "grounding out" before it reaches the circuit's load (the power mirror motor). The load in any electronic circuit, whether it be a light bulb, a power window motor, or whatever, serves as the circuit's RESISTANCE. So basically, the mirror circuit is bypassing the load and going straight to ground without any resistance, and according to ohm's law when resistance goes down current goes up, and the excessive current is blowing your fuse every time you attempt to activate it. A chronically blown fuse is the telltale sign of this, and that fuse most likely controls several circuits (including your cig lighter) as most do. The cause of this is almost always from a wire rubbing against something metal and wearing through the insulation. Get ahold of a wiring diagram for your car and start checking for chafed or pinched wires somewhere between the circuit's fuse and the power mirror motor. Good luck.[BooZted Z31]

*1988 NISSAN 300ZX (CT26 turbo, CXracing intercooler, 3" exhaust, k&N, Z32 twin-turbo fuel pump, Prothane bushings, Dunlop SPsport 8000, rebuilt/polished head w/4 angle valve job, etc